Networks

Networks

1. LAN's or local Area Networks

   • LAN's are usually based on small geographical areas, they are usually wired or done through WI-FI and used in schools, businesses ect

2. WAN's or Wide Area Networks

   • WAN's are usually used for large geographical areas they also connect LAN's globally

3. Many things affect the speed of a network like bandwidth which is the amount of data that can pass down at a certain amount of time

4. Network Hardware

   • NIC's, Switches and routers
     • A NIC or Network Interface Controller is a piece of internal hardware that allows the device to connect to the network
     • Routers are responsible for transmitting data between networks
     • Switches connect devices on a LAN
   • Cables
     • Ethernet cables are used to connect devices in a LAN
     • Coaxial cables are made of a single copper wire surrounded in insulation
     • Fibre optic cables are for transmitting data as light
   • WI-FI is standard for wireless it uses two radio frequency bands - 2.4 GHz and 5 GHz
   • Wireless uses radio waves to transmit data

5. Client-Server and Peer-To-Peer Networks

   • Client-Server Networks are run by a central server
   • The clients send requests to the server
   • In P2P Networks all devices are equal and connected togeather

6. Network Topologies

   • In a Star Topology all devices are connected to the center
   • In a Bus Topology all devices are arranged in a line
   • A Ring Topology data runs round in a ring
   • In a Mesh Topology all devices are connected togeather
   • A partial Mesh Topology is were the majority of devices are connected togeather

7. Network Protocols

   • Networks need Protocols to set rules
   • MAC Addresses
     • All network-Enabled devices are assigned with a individual MAC address
     • Mac addresses are 48 or 64 bit
   • IP Addresses
     • Communications between different networks use IP Addresses
     • IP addresses are used when sending data between TCP/IP networks
   • Data is sent between networks in Packets
   • Packet switching is used to Direct data
   • TCP/IP Dictates how data is sent between networks
   • Layers
     • Layer 4 Application layer - Turning data into websites ect
     • Layer 3 Transport layer - Controlling data flow
     • Layer 2 Network layer - Makes Connections
     • Layer 1 Data Link Layer - Passing data over a physical network

8. The Internet

   • DNS or Domain Name Server Translates a Domain Name into a IP
   • WWW is a Collection of websites that are hosted on web servers
   • The Cloud uses the internet to stores files and applications
   • Virtual Networks are software-based networks